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Crazy idea. 32GB RAM modules in a cMP. Anyone tried this?
- Thread starter William Payne
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never said it was called X, i call it X & wrote is as such...
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cDMP (Cheese Grater Dual Mac Pro)
This exists only in your mind.
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& yet my mind DOES indeed exist......
How is all this related the topic about the ram exactly?
If you used the correct terms, no one would misinterpreted or replied alerting you…
[doublepost=1552255665][/doublepost]
& yet my mind DOES indeed exist......
How is all this related the topic about the ram exactly?
It's very simple - if you want to discuss something on the forum, it's better to use the common nomenclature than to speak in a code that only you understand.
There are lots of typos (and English as a second, third, or fourth language) here - so it's quite reasonable to interpret "Windows X" as a typo for "Windows XP", not as a neologism for "Windows 10".
Windows 10 Pro 64 bit supports up to 512 GB. Can you test 6x32 GB and 8x32 GB?
about time - someone with a reasonable question/request
I will be doing so later on this afternoon (i've got to head the the gym first)
But yes i am patiently waiting to test all 8 ram modules & also run some sort of memtest on them as well
thx
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Understood, but i've always called Windows 10 - Windows X (just as an FYI for my defence)
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sounds like you've got a grudge, i don't have one ;-)
so far not the best...
when all 8 slots are filled with 32GB ram modules, 10.13.6 wont boot - just stays on the Apple logo with no progress bar movement at all (in fact the progress bar doesnt even appear)
I havent tested this with Mojave as of yet as i've just cloned installed it onto the 2nd partition.
With respects to Win 10 Pro x64 the ram only shows as 224GB - thats a little short of the 256GB thats actually installed.
I'll post some pics below
[doublepost=1552343494][/doublepost]OK, so below are pics of the cMP running windows 10 Pro x64
there's 6 x 32GB ram modules installed with this test
Total ram showing is only 160GB - not too sure if i have a faulty module, but i will be running further tests
[doublepost=1552343687][/doublepost]With this test, all the 8 memory slots are occupied with 32GB ram modules
Only 224GB showing, once again not too sure if i have a faulty module(s)....
I'll be doing more tests over the next few days however i've got other work commitments on at the moment.
I'll try update ASAP
Just as an FYI, i've also cloned installed 10.14.2 & I've updated the software to 10.14.3
did this with 2 x 16GB ram modules to avoid any unexpected shutdowns/restarts etc
So far these tests are just preliminary.
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Here is a warning from OWC even though it is for their modules bare in mind mixing different module types might not work.
"OWC p/n OWC1333D3MPE8GB (8GB modules) and OWC1333D3MPE16G (16GB modules) require that all installed modules be of the same p/n OWC 8GB and/or 16GB modules. Other existing Apple or 3rd party 1GB, 2GB and 4GB modules are not supported for use with these kits and need to be removed when these modules are added."
It is strange that Windows does not recognize all modules though
"OWC p/n OWC1333D3MPE8GB (8GB modules) and OWC1333D3MPE16G (16GB modules) require that all installed modules be of the same p/n OWC 8GB and/or 16GB modules. Other existing Apple or 3rd party 1GB, 2GB and 4GB modules are not supported for use with these kits and need to be removed when these modules are added."
It is strange that Windows does not recognize all modules though
not too sure if thats meant for me but i am in NO WAY mixing OWC's memory modules
In fact these memory modules are NOT from OWC or any of its affiliates.
Also the ram modules are all the same part number
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You can easily test each modules one by one and just follow this red LED. If it's showing even with one module then it's faulty - just run memtest on it and it should show errors right away.
Otherwise we are hitting a wall here. I think your CPU might be a limit - E5520 should support no more than 144 GB: https://ark.intel.com/content/www/u...20-8m-cache-2-26-ghz-5-86-gt-s-intel-qpi.html
Otherwise we are hitting a wall here. I think your CPU might be a limit - E5520 should support no more than 144 GB: https://ark.intel.com/content/www/u...20-8m-cache-2-26-ghz-5-86-gt-s-intel-qpi.html
Cheers mate - thanks for the heads up (Yes i am running 2 x 2.26GHz Xeon's) which are in the Mid 2009 Mac Pro 4,1 --> 5,1 firmware update
I've got a 2 x 2.4GHz Xeon Mid 2010 5,1 complete/seperate setup (Also as previously mentioned 2 x 3.46GHz X5690's CPU's waiting to get installed)
I'll try the same tests in that machine, I've got a few things on but will definitely try my best to get my findings out on to this thread ASAP
Flex mode is NOT dual channel.
The slot 3 and 4 (also 7 and 8) has its OWN channel. It's impossible to run all 8 DIMM with just dual channel on cMP.
quite right, but its still way much more memory than the 6 x 16GB (96GB)
I too myself personally wont be using all 8 slots, i will be aiming for 192GB max via 6 memory slots.
So far i've got 4 x 32GB + 2 x 16GB (160GB Total) to work OK with the 2 x 2.26GHz 4,1 --> 5,1
But ill have a play on Thur/Fri/Sat when i've got more time on my hands
I'll run some benchmarks as well & post pics etc
ramdisk is not faster than nVME ssd. Even in raid. But surely if you have a lot of unused RAM then you can put it to useful work.
Geekbench memory speed tests often don't reflect real application performance. (Geekbench effectively disables the caches for the memory tests, real applications exploit the caches.)
Here's a good overview of how little most apps were affected by using 1 - 2 - 3 - 4 memory channels on an MP6,1
@Kon_Kipa
Looking at your 8x32GB setup, your memory timings under windows are 6 6 6 15 which is 800 MT/s and your cycle time is 10 ns.. Your memory is effectively running at DDR3 800 or PC3-6400 speeds.
Stick with 6x32GB (192GB) if you manage to get them to load under your 5,1/X5690 build or as you planned 4x32GB and 2x16GB (160GB). Aim for 1066 MT/s data rate as you cannot achieve 1333 MT/s data rate (which is the default for the 5,1) with that amount of memory installed.
Your 5,1/X5690 benchmarks and memory transfer speeds are going to suffer and be lower.
Looking at your 8x32GB setup, your memory timings under windows are 6 6 6 15 which is 800 MT/s and your cycle time is 10 ns.. Your memory is effectively running at DDR3 800 or PC3-6400 speeds.
Stick with 6x32GB (192GB) if you manage to get them to load under your 5,1/X5690 build or as you planned 4x32GB and 2x16GB (160GB). Aim for 1066 MT/s data rate as you cannot achieve 1333 MT/s data rate (which is the default for the 5,1) with that amount of memory installed.
Your 5,1/X5690 benchmarks and memory transfer speeds are going to suffer and be lower.